Choosing the correct pond filter media is a tremendously important step in any pond design.
Filter media can refer to the interior components of mechanical filters, but the term is more commonly associated with biological pond filters. Biological filters convert harmful fish waste and organic materials into beneficial nitrates that are absorbed by aquatic plants. This conversion is accomplished by nitrifying bacteria. To maximize efficiency, bacteria are concentrated inside the biological filter. As pond water circulates through the filter, all of the fish waste in the pond is exposed to the bacteria and begin converting into nitrate.